TRANSDUCTION OF HEMODYNAMIC SIGNALS INTO VASCULAR CELLS

制定有效的预防和治疗方案， 心血管疾病，重要的是要了解控制的 血管内皮的功能状态。 血液流动的变化， 压力改变了内皮细胞（EC）的功能状态， 在现场自然地受到物理力的作用。 因此，定义 物理力量在维持正常和 产生病理性EC行为是重要的。 剪应力， 与血流产生的EC相切的方向被认为是 对内皮损伤最大的机械力。 是否 剪切应力的脉动变化作为刺激不同于稳定的 剪切应力未知。 本研究将分析 自适应EC响应稳定的剪切应力，并比较这些与 对脉动剪切应力的反应。 血液动力学信息如何通过细胞膜传递 以及如何将该信息传送到细胞的其他部分， 追究 细胞对蛋白质变化的反应 将研究合成。 具体目标遵循以下顺序： 刺激和反应，测试以下假设：1。的 剪切应力信息的转换包括离子的改变， 导致膜超极化的通道，2.的增加 胞浆钙离子作为剪切传递的第二信使 压力信号，以及3.剪切力改变了 特定蛋白质将鉴定蛋白质，并研究其动力学。 将研究由剪切应力产生的这些蛋白质的变化。 长期目标是了解EC蛋白的适应性反应 剪切应力，并研究转导事件如何改变 合成这些蛋白质。 这些研究将涉及连续测量膜 电位和胞浆钙使用分光荧光染料， 同位素流出 放射性标记的蛋白质将通过二维凝胶进行研究 电泳、荧光照相术、凝胶的数字分析、分级分离， 抗体反应性和肽测序。 EC异常可能导致动脉粥样硬化、血栓形成， 止血障碍，以及炎症，免疫反应性和 肿瘤发生 剪切应力如何改变EC功能将阐明这些 疾病过程。

To develop effective preventative and therapeutic regimens for cardiovascular disease, it is important to understand control of the functional state of the vascular endothelium. Changes in blood flow and pressure alter the functional state of the endothelial cells (EC), which are naturally subjected to physical forces in situ. Thus definition of the precise roles of physical forces in maintaining normal and in producing pathological EC behavior is important. Shear stress, the force tangential to the EC resulting from blood flow is considered to be the mechanical force that is most injurious to the endothelium. Whether pulsatile variations in shear stress differ as a stimulus from steady shear stress is unknown. This research will analyze the mechanisms of adaptive EC responses to steady shear stress, and compare these with responses to pulsatile shear stress. How hemodynamic information is transduced across the cell membrane and how this information is then conveyed to other parts of the cell will be investigated. How the cell responds in terms of changes in protein synthesis will be investigated. Specific Aims follow a sequence of stimulus and response, testing the following hypotheses: 1. that transduction of shear stress information consists of alterations in ion channels leading to membrane hyperpolarization, 2. that an increase in cytosolic calcium acts as a second messenger for transduction of shear stress signals, and 3. that shear stress changes synthetic rates of specific proteins. The proteins will be identified and the kinetics of change in these proteins produced by shear stress will be investigated. The long term goal is to understand the adaptive response of EC proteins to shear stress, and to investigate how transduction events alter synthesis of these proteins. These studies will involve continuous measurement of membrane potential and cytosolic calcium using spectrofluorometric dyes and isotopic efflux. Radiolabelled proteins will be studied by 2-D gel electrophoresis, fluorography, digital analysis of gels, fractionation, antibody reactivity, and peptide sequencing. EC abnormalities may contribute to atherosclerosis, thrombosis, hemostatic disorders, as well as to inflammation, immune reactivity and tumorigenesis. How shear stress alters EC function mill elucidate these disease processes.